My wife has a 2006 Cobalt with the 2.0 engine. Last spring the engine light came on. I took it to Tunex and the code was P0326 Knock Sensor 1 Circuit Range/Performance (Bank 1 or Single Sensor). The car was running fine and the technition suggested that we reset the engine light and see if it comes back on. It did not come back on unitll a month ago. I have noticed the last coupel months that the gas milage has dropped about 8 miles per gallon and sometimes at Idel the RPMS will drop a bit. Other than that the engine sounds fine. The engine light will stay on for a couple days then go off for more than a week. I took it to auto zone and they said it was the same P0326 Knock Sensor code.

Does this sound like the Knock Sensor is bad? How easy of a job is it to repealce the Knock Sensor myself? Where exactly is it located?

Thanks for any help!

Mark

 

The knock sensor is a pita to get to, its located on the front of the engine....i replaced it with the car jacked up, it might've been easier to replace it from the top however u might have to take the supercharger and manifold out to reach it...

 

I know this is an old post but if anyone's still curious, it located on the front side of the engine, as previously stated, right behind/above the starter (side closest to the trans). Its basically just a bolt holding down what looks like a thick groundstrap. As far as the code, the most common cause is bad gasoline (such as using regular octane vs premium). In my case I just recently finished rebuilding my engine and putting it all back in, so the half tank of gas I ha in it had been sitting for over 6 months and the gas had gone bad. I kept getting the same knock sensor code (I have my own code scanner). I just added some octane booster and kept resetting the code whenever it came on until I could burn up the rest of the old gas. After I filled her back up with fresh premium gas everything was well.
Btw I'm referring to an 05 cobalt ss/sc. Hope this helps